| What is LID? Low Impact Development is an approach to environmentally friendly land use planning. It includes a suite of landscaping and design techniques that attempt to maintain the natural, pre-developed ability of a site to manage rainfall. LID techniques capture water on site, filter it through vegetation, and let it soak into the ground where it can recharge the local water table rather than being lost as surface runoff. An important LID principle includes the idea that stormwater is not merely a waste product to be disposed of, but rather that rainwater is a resource.
Where should LID be used? LID can be applied to new development, urban retrofits, and redevelopment / revitalization projects at many scales. At a small scale, LID techniques can be used to better handle rainfall for a single family lot through rain barrels and rain gardens. At a larger scale, proper site design in combination with many landscaping and infiltration techniques distributed throughtout a subdivision cumulatively improve rainfall and run off management.
Conventional Development vs. LID: Conventional development techniques often clear all trees and valuable topsoil from a site and re-grade it so that all water ends up in one large detention basin. Resulting problems include loss of recharge, increased water temperature, decreased water quality and higher runoff volumes.
The LID approach protects the natural ability of the site to capture precipitation, keep it clean and allow it to recharge the local water table. This is achieved by applying a suite of tools including:
- Planning: preserve the site's natural features such as wetlands, native vegetation, flood plains, woodlands and soils to the greatest extent possible;
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The Preserve considered many natural features that were saved by laying out the lots after identifying existing features to be maintained. |
- Landscaping: plant native vegetation in buffer strips and in rain gardens (small planted depressions that can trap and filter runoff);
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Vegetated areas will receive storm water which filters through rain gardens. |
- Prevention: use vegetated areas to slow down runoff; maximizing infiltration and reducing contact with paved surfaces;
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Roads in the Preserve will have no curbs, a reduced width, and will be bounded by extensive undisturbed vegetation. |
- Innovating: reduce impervious surfaces wherever possible through alternative street design, such as omission of curbs and use of narrower streets, and through use of shared parking areas.
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Use of a roadside rain garden in a residential development to manage storm water.
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What are the benefits of LID at The Preserve at Oak Hill?
- Stormwater Management: LID techniques can help us reduce runoff and nonpoint source pollution - our biggest source of pollution to water bodies.
- Aesthetically Pleasing: LID practices are often more cost effective and aesthetically pleasing than traditional, structural storm-water conveyance systems.
- Lower Maintenance: LID measures reduce municipal infrastructure and are therefore lower in maintenance than conventional, structural storm-water controls. (EPA Low Impact Development, a Literature Review, 2000). Many LID techniques can be maintained using traditional landscaping practices.
- Cost Effective: LID techniques require less constructed infrastructure, increase the value of properties, reduce irrigation costs and often increase the number of units which can be developed on a site.
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